# About Active Directory Objects and Recipients

In the Active Directory, Exchange recipients are stored as one of the following native Windows objects in the Domain container:

- Mailbox. In the Active Directory, a Mailbox is a mailbox-enabled user of Windows 2000 Server. When a user is mailbox-enabled, there is an e-mail address indicating the Exchange server to which the user's e-mail should be routed. The user must then use e-mail client software to connect to the Exchange server and receive e-mail.

  Existing Exchange mailboxes are replicated into the Active Directory as users or contacts.

- Distribution Lists. Windows groups are represented as distribution lists in the Exchange directory. E-mail received for the distribution list is routed to the e-mail address of each group member. Mailbox-enabled users can also send e-mail to the distribution list.
- Custom Recipients. Mail-enabled users or contacts are represented as custom recipients in the Exchange directory. When a contact is mail-enabled, that object has an e-mail address used by Exchange to properly route the e-mail.

Note:

Before enabling e-mail attributes for any Active Directory objects, you must first create a Connection Agreement in the appropriate organizational unit. Then replicate the selected object(s) into the Exchange directory. All organizational units that are under an organizational unit with a Connection Agreement will also be replicated. If you are joining an existing Exchange server that already contains recipients, you must replicate those recipients to the new Active Directory using a Connection Agreement in ADC.